Your daily forecasts from Boards.ie weather forum (NO CHAT)

Wednesday, 7 February, 2018

Forecasts for Ireland


TODAY ... A few sunny intervals in east and south, becoming mostly overcast later as cloud already spreading into Connacht reaches the rest of the country, followed by outbreaks of sleet or wet snow turning to rain (starting as rain near the west coast), as temperatures slowly recover to more normal values near 7 C in a developing southwesterly wind of 50-70 km/hr.

TONIGHT ... Any remaining sleet in Leinster or east Ulster turning to rain, with about 5 to 10 mm expected in general before more showery or drizzly conditions develop towards morning, temperatures steady 7 to 9 C, winds west-southwest 50 to 80 km/hr.

THURSDAY ... Milder for a time with rain or showers, highs near 8 C, possibly reaching 10 C south coast briefly, then turning much colder from the northwest, with snow or sleet showers returning as winds veer to the northwest, with temperatures falling rapidly to near 1 C. Winds west to northwest about 50 to 80 km/hr adding chill especially afternoon and evening. Some heavy snow showers likely in Donegal, and north Connacht.

FRIDAY ... Windy and cold with passing wintry showers, lows near -2 C and highs near 5 C. Once again turning milder in the evening with sleet turning to rain developing.

SATURDAY ... Turning milder again with southwest winds 50-70 km/hr and rain at times, highs near 11 C, then much colder late in the day as winds veer to westerly 60-90 km/hr. Wintry showers overnight into Sunday with renewed snow accumulations in the north and west.

SUNDAY and MONDAY ... Windy and cold with occasional snow or hail showers. Highs about 4 C. Winds generally westerly about 50-70 km/hr.

TUESDAY ... Windy and milder with rain briefly, but once again, this warm sector will only last a matter of hours before colder air blasts in from the northwest. This next push may be stronger with widespread snow showers likely and temperatures struggling to reach 2 C in bitter northwest winds.

Further down the road, this cold spell might have a brief milder interval before a change to easterly flow and a brighter, less windy variety of cold with better snow chances for the east coast, although even this pattern itself is not guaranteed yet, as it is not showing on all guidance. Very cold air is filtering into Scandinavia already from northwest Russia and temperatures as low as -35 C have been reported in northern Sweden and Finland, so there is some potent cold air available if the winds do turn in that direction. The Baltic Sea and to some extent parts of the North Sea also are both running warmer than normal which would fill any easterly flow with a lot of moisture. And we have not seen much easterly flow this winter but a "stratospheric warming" event is forecast and this can create blocking at higher latitudes necessary to get the winds into that direction. Let's say the chances are fairly good for a spell of easterly winds, while not a certainty yet.

My local weather was pleasant (for a change) with the sun making a rare appearance (this is a very sunny location from March to October but winter cloud is the norm due to inversions over the valleys here). It was relatively mild by afternoon reaching 4 C. However, it has begun to snow this evening and we're expecting 20 cms on Wednesday, possibly mixing with rain at times. Avalanche danger is high, a local highway was closed for two days recently while crews cleared a massive snowslide (posted a picture of this in the snow and cold weather thread).

Snow is developing in the Ohio valley and will spread into the inland northeastern U.S. late today, forecasts are calling for sleet or rain on the coast but 5 to 15 cms of snow inland, and from Boston north along the coast also.

There is still very little active weather in Australia today, but parts of Japan have received heavy snowfalls in the past few days and it's unusually cold in many parts of east Asia as that huge Siberian high recently split, part of it ended up in Finland and another larger part spread southeast into Mongolia and northeast China. The timing is good as the Winter Olympics begin on Friday in South Korea at a site that needs at least some artificial snow, so a mild spell would not have been great news there.

Friday, 9 February, 2018

Forecasts for Ireland


TODAY ... Windy and cold with passing wintry showers, with snow less frequent in the mix by afternoon, sleet or hail more likely then, but all through that some sunny intervals as well with temperatures slowly rising to about 5 or 6 C by late afternoon with the last of any sleet turning to rain by early evening, winds backing to southwest and increasing to 70-100 km/hr, some strong gusts near west coast by evening.

TONIGHT ... Windy with 5-10 mm rainfalls, winds southwest 70-100 km/hr, temperatures continuing to edge upwards towards 9 C.

SATURDAY ... Windy and mild although in the strong winds not feeling all that warm, temperatures steady near 10 C, rain easing to showers but squally at times with hail. There may be an interval of very strong winds especially through central counties mid-afternoon, details on this may change so stay tuned as it could be briefly severe (gusts to 120 km/hr possible). It will then turn much colder as winds veer rapidly to northwest 70-100 km/hr with wintry showers returning by evening, temperatures about 2 C by then.

SUNDAY ... Windy and very cold with snow showers likely, 1 to 3 cm accumulations in some places (3 to 6 cm higher ground northwest), winds westerly 60 to 90 km/hr and temperatures steady 2 to 5 C.

MONDAY ... Windy and cold with intervals of sleet likely, some snow accumulations on hills, despite southerly winds 50-80 km/hr (and another interval of very strong winds possible), highs near 6 C.

TUESDAY ... Rain or sleet, snow on hills, in northeast winds as low pressure forms to the south, but not quite enough cold air feeding in to make this a snowfall event (at present reading anyway), highs near 7 C.

WEDNESDAY ... Very windy and cold with showers of sleet, hail and snow developing in gale to storm force southwest winds 70-120 km/hr (strongest winds in north and west). Temperatures steady near 7 C but falling off during heavier bouts of wintry showers.

OUTLOOK ... Very unsettled and rather cold once this mid-week windstorm situation passes, little change in the slightly below normal temperature trend. The longer term indications remain very unclear beyond next week with cold influences from east and northwest seeming to want to battle for dominance, but either way it will probably stay quite cold.

My local weather on Thursday was foggy with light rain and a high near 2 C, some snow fell at times last night but the system then weakened and is now falling apart as colder air pushes in from the north. A snowfall of 10-20 cms has developed over much of the lower Great Lakes region from a frontal boundary that is bringing arctic air of about -10 C up against much milder Pacific air masses near 10 C in the Ohio valley and central plains states. This will push into northern New England over the weekend leaving the east coast in the milder air mass for several days.

Australia remains largely dry and sunny, although rather cloudy around Sydney in the past few hours.

UPDATE _ Sat 10 Feb 2018 _ 5:30 p.m.
___________________________________

Low pressure is gradually developing over western counties at this time, which may mean that the strongest wind gusts will occur over eastern counties later this evening. There is still some time available for strong gusts to develop in Galway (some reports around 80 km/hr already) but more likely for gusts over 100 km/hr would be Dublin and Meath by about 9-10 p.m. ... as this zone of strong winds expands through central counties in the next two hours, gusts to about 90 km/hr are likely in east Galway, Roscommon, Offaly, north Tipps and later into Kildare and Westmeath. Gusts to about 110 km/hr are possible in Dublin, Kildare and Meath later this evening.

There is also a slight risk of a gusty thunderstorm further south along a developing frontal boundary that is currently in northeast Cork and western Tipperary; this may produce a few strong gusts and hail in counties of the inland southeast this evening.

As to the rainfall alert, most of that rain has already fallen except in the eastern half of the country where northern sections still have about 10 mm left to fall, amounts further south more like 5 mm additional. Watch for some flooded roadways in Connacht (central Galway at least, according to reports on the event discussion thread). Amounts have been heavy from about Newport to Cavan.

Monday, 12 February, 2018

Forecasts for Ireland


TODAY ... Breezy to windy, sunny intervals with passing wintry showers, and while still cold this morning, turning somewhat milder by afternoon when any remnant snow or sleet showers should be mostly confined to higher elevations and rain will develop in strong south to southwest winds that may peak around 70-110 km/hr by evening. Temperatures will continue to climb back slowly towards 7 or 8 C.

TONIGHT ... Rain will end with an interval of sleet or snow that might require a forecast update later this afternoon, as conditions appear marginally favourable for some accumulations in parts of Leinster overnight, with clearing further west, as winds ease and shift more to a westerly direction 40-60 km/hr. Lows by morning will be close to 1 C.

TUESDAY ... Windy and colder for the first part of the day with snow showers, then as winds back to southerly, rain may develop especially over northwestern counties, with moderate south to southwest winds 50-80 km/hr by evening. Lows near 1 C and highs near 8 C. Rain will be more persistent Tuesday night in strong south to southwest winds 50-80 km/hr.

WEDNESDAY ... Windy and somewhat milder for the morning hours, then turning colder by afternoon and evening. Very strong winds could brush outer coasts of Connacht and Ulster but for most, expect southwesterly 60-90 km/hr, with intervals of rain turning more to sleet or wet snow in some higher locations by late in the day.
Lows near 5 C and highs near 8 C.

THURSDAY and FRIDAY are looking quite cold with passing wintry showers, moderate westerly winds, highs about 5 to 7 C.

The weekend of 17th-18th and perhaps several days after that will be influenced by building high pressure, this is a slight change from the easterly scenario that was discussed yesterday and all guidance seems to favour this now so it tends to be a compromise between those formerly different outcomes, so while it will be rather cold under this high pressure, with sharp frosts likely, there won't be enough of an easterly flow as it now appears to create much potential for wintry showers on the east coast. The situation beyond this period of settled weather is quite uncertain and could still go either way (back to milder southwesterly flow, or eventually more of a draw from the east if this high were to drift back out to the west towards the end of the month).

My local weather was partly cloudy and cold with highs only reaching -2 C, and it's clear and very cold at the present time.

Tuesday, 13 February, 2018

Forecasts for Ireland


TODAY ... Windy and cold with a few outbreaks of snow or sleet, more likely in the west and north but not exclusively there, with the potential for 1 to 3 cm brief covering of snow, some icy roads as a result. There will also be some sunny intervals in the mix, and later on more of a wintry mix of showers as highs reach about 4 to 6 C in gusty westerly winds 50 to 80 km/hr. By late afternoon and evening, these winds will have backed into a south to southwest direction and some outbreaks of rain are likely as temperatures will remain steady, but sleet could develop on higher ground in the north ahead of the milder air.

TONIGHT ... Windy with intervals of rain, temperatures steady 5 to 7 C, winds south to southwest 60 to 90 km/hr.

WEDNESDAY ... Rain becoming more showery during the morning, peak temperatures likely around 10 a.m. to noon (8 to 11 C) when winds will begin to veer more westerly, then temperatures slowly falling during the afternoon to 4 or 5 C with showers becoming somewhat wintry again at least in higher parts of the west and north. Very strong gusts are possible but may stay off the northwest coast.

THURSDAY ... Partly cloudy, passing wintry showers, cold. Morning lows -1 to +2 C and afternoon highs 4 to 7 C. Winds westerly 50 to 80 km/hr.

FRIDAY ... Sunny intervals, isolated showers, some wintry on hills, not as windy, lows -2 to +2 C and highs 5 to 8 C.

WEEKEND OUTLOOK ... Generally settled weather for the weekend as higher pressure builds up over Ireland, some sunny intervals both days, morning frosts, and highs near 7 or 8 C.

FURTHER OUTLOOK ... All guidance now agrees a colder easterly spell will develop as the weekend high drifts off to the north and northwest, and temperatures will fall back to near freezing in the daytime and -6 C or lower at night if the current set of maps is correct, with potential for snow in eastern counties, in particular around Thursday or Friday (22nd-23rd). This is not a guaranteed outcome yet, but with all global models showing similar outcomes, we can say that there is moderate confidence in this wintry outlook. What is less certain is how long that spell might last once it arrives, the one model that goes past ten days has it breaking down within a few days but that is really a low confidence forecast at this stage.

My local weather on Monday was sunny and rather cold with highs near -1 C, snow cover basically frozen at the surface and roads bare and dry but some ice where slush from last week has frozen. The weather pattern across North America has gone relatively quiet, we're expecting an increase in cloud all day Tuesday followed by about 5 to 10 cm of new snow Tuesday night.

Thursday, 15 February, 2018

Forecasts for Ireland


TODAY ... Frequent wintry showers may drop snow or sleet at times, but it can also rain as temperatures fluctuate between 2 and 6 C, with hail also in the mix. Some sunny breaks will occur between the showers and a few places might have longer sunny spells, most likely in the lee of mountains in the south and southeast as winds will remain blustery from the west at 50-70 km/hr.

TONIGHT ... Some remnant snow showers but clearing gradually in parts of the east and south to allow some frost, lows -2 to +2 C.

FRIDAY ... Partly cloudy, not quite as cold, a few showers but amounts generally less than 2 mm, highs 6 to 9 C.

SATURDAY ... Some rain at times, mostly near west coast and across Ulster and north midlands, but eventually a few outbreaks in the south as well, highs reaching about 10 C.

SUNDAY ... Partly cloudy and mild, highs 10 to 12 C.

MONDAY to WEDNESDAY will continue settled and rather mild at least in western counties, there may be a slight downward trend in temperatures for the inland south and most of the east, but highs will remain generally at least 8 C if not 10 to 12 C in the west, and there should be decent amounts of sunshine and only a few very isolated showers if any rain at all.

FURTHER OUTLOOK ... We are back to the "battle of the models" as the European model seems to want nothing to do with colder air moving west or south towards Ireland, in fact this model returns to rather mild southwesterly patterns after the consensus of high pressure early next week, whereas North American models are quite consistent with easterly flow developing some time between mid-week and the end of next week, then that lasting a few days but coming into conflict with returning milder air trying to push it back into Britain and central northern Europe. If I had a time machine or a crystal ball I could say which outcome is right (maybe none of them are?) but we haven't seen a cold easterly spell yet this winter really, so maybe that's the sentimental favourite.

My local weather saw the heavy snowfall ending before dawn, then slow and partial clearing with temperatures steady around -1 C. We had a nice new covering of 20 cms which has returned our overall snow depth to 35 cms for now and cleaned up the appearance of the huge snowbanks all around the town from the non-stop snow clearance operations in the past month (we have some snowbanks over 20 feet high in some places). Going up into the higher elevations on Thursday to see how it looks up there after what was likely 30 cms new snow, may win a Darwin award for this.

Meanwhile, in the South Pacific, severe cyclone (hurricane) Gita is now south of Fiji, after doing considerable damage on the 12th in Tonga. This cat-4 (Australian system) 950 mb storm is moving due west and has missed most of Fiji although it gave one small outlying island a lashing yesterday. I'll keep an eye on its future course as these sometimes recurve southeast towards New Zealand. The damage in Tonga included flattening parliament buildings, if you've ever seen the Tongan rugby team you'll know that they are safe.

Saturday, 17 February, 2018

Forecasts for Ireland


TODAY ... Some early frost and fog patches, becoming partly cloudy and mild by later morning, highs 8 to 12 C.

TONIGHT ... Some clear spells at first in east and north may allow a slight frost to form, but overcast later with rain moving into south and west, temperatures rising everywhere, reaching 10 C in southwest, 4-6 C east and north.

SUNDAY ... Morning rain and mist, some clearing later, mild, highs near 12 C.

MONDAY ... Partly cloudy, mild. Highs 10 to 13 C.

TUESDAY ... Some early rain then clearing, a little colder, highs 7 to 9 C.

OUTLOOK ... No clear solutions yet so the choice at the moment seems to be between modified colder weather with slight frosts and daytime highs 4 to 7 C, or the more severe form of cold still prominent on some models again this morning, with the risk of snow in eastern and northern counties by late next week.

These different outcomes are dependent on whether high pressure forming near Ireland around Monday-Tuesday will be the dominant feature, or whether it will get linked up into stronger and much colder arctic high pressure that some guidance places over north-central Scandinavia. This has to follow a rather complicated sequence of events involving high pressure currently very close to the north pole moving across into northern Russia in the next four days. So we are basically waiting to see what happens with this, if the pressure starts to rise steadily around Murmansk and Helsinki next week, then this very cold spell becomes a strong possibility. If things remain less dramatic (average sort of cold weather for that region) then the west European high will probably be all we have to work with, and it needs to link up to something further east to get any sort of really wintry conditions to move west.

My local weather produced 5 to 8 cms of snow during the morning and that continued as light flurries up to the present time, with heavier snow about ready to begin for most of Saturday (expecting about 20 cms more now). The temperature has been close to zero C all day. In eastern North America, some very mild weather has come and gone in the past two days and it's getting back to more average mid- February temperatures now although remaining largely dry.

Cyclone "Gita" in the South Pacific appears to be weakening almost below hurricane strength now and has started to recurve south, later southeast to brush past the northern tip of New Zealand by Monday or so. Looks like there is also tropical cyclone activity near the north coast of Western Australia.

Monday, 19 February, 2018

Forecasts for Ireland


TODAY ... Mostly cloudy and misty to start, some brighter intervals developing around late morning, with scattered outbreaks of light rain following by afternoon (2 to 5 mm expected). Highs 10 to 13 C.

TONIGHT ... Drizzle and fog at times, lows 3 to 6 C.

TUESDAY ... Gradual clearing, cooler. Light to moderate northerly breezes. Highs about 8 C.

WEDNESDAY and THURSDAY will feature some sunshine each day with morning frosts and fog patches, and it will be rather cold although some west coast locations may warm up to around 10 C, otherwise highs about 6 to 8 C, and morning lows about -2 to +1 C.

FRIDAY and next WEEKEND are likely to see increasing southeasterly winds and a slight drop in temperatures each day, reaching about 4 C by Sunday. There will likely be considerable cloud and some brief sunny breaks, morning fog patches and slight frosts.

If colder weather follows as some guidance continues to depict, winds will be brisk easterly and there could be snow near the east and south coasts as well as in parts of Ulster. This colder spell may push temperatures as low as -1 C in the daytime but this is not locked in yet, there is an equal chance that the readings will stay about the same as the weekend (4 to 6 C) with less chance for snow. I am hoping this situation will become clearer through model consensus by mid-week but sometimes these wintry spells leave us uncertain until much closer to "show time" (or snow time?). If severe cold does develop, Monday 26th to the first few days of March would appear to be the time frame.

My local weather on Sunday was bright and cold although rather cloudy, the sun trying to get through dense higher level cloud layers, but no further snowfall, and highs only -3 C. Some wet snow has fallen in parts of the northeast U.S. over the weekend, followed by colder weather there.

Wednesday, 21 February, 2018

Forecasts for Ireland


The risk of severe cold next week now appears to be just the opening phase of what could be quite a long cold spell, and there should be enough clear skies on some nights to guarantee that some particularly low overnight temperatures will develop during this spell. The chances for snow are more difficult to assess, there are various scenarios in different global models that could produce snow in parts of Ireland, and Leinster, east Ulster, and the south coast probably have the higher risks. We don't expect a lot of clarity on snow potential until the cold air settles in, frankly the models seem to be taking small clues and amplifying their significance but that's not to say the overall idea of a significant cold spell is faulty, just the details on offer (still six or seven days away).

TODAY will have some morning fog and mist patches, with sunny spells to follow, but a general increase in cloud during the day, and with light southeast winds the morning chill may not quickly dissipate, but eventually highs will reach 6 to 9 C.

TONIGHT will bring mostly cloudy skies but any clear patches in north Leinster or east Ulster might promote local frost and fog, otherwise expect lows 2 to 5 C.

THURSDAY and FRIDAY will be similar days, partly cloudy, mostly dry, with moderate southeast winds, milder in the Atlantic coastal counties than further east, with highs 8 to 10 C west, 5 to 7 C east, and slight frosts each morning inland, but lows around coastal and urban areas just above freezing. Winds southeast 40 to 70 km/hr will sometimes feel rather cold.

WEEKEND OUTLOOK ... There is some uncertainty on the timing but most of the weekend will continue to be transitional as the current cool dry air mass awaits eviction by the stronger westward-moving very cold air from Russia. So it seems most probable that the weekend will feature highs near 6 C and slight to perhaps moderate frosts each morning, with winds remaining southeast 40 to 70 km/hr. There could be some sunshine each day but eventually more cloud by late Sunday with chance of sleety drizzle as colder air arrives.

NEXT WEEK looks very cold with frequent dry spells and wintry sunshine, but the ongoing risk of localized snow especially in Leinster, coastal south, and east Ulster. Further west, not quite as severe and less chance of wintry showers at first. This severe cold will be accompanied by east winds 50 to 80 km/hr at times, although inland more like 30 to 50 km/hr. Daily highs will be in the range of -1 to +3 C and overnight lows by Tuesday could be as low as -9 C inland, -4 C in more temperate coastal areas. Later on, towards 1-2 March, winds may turn more northeasterly at times with passing disturbances dropping snow or sleet.

This cold spell could dig in and continue for quite a long stretch, with perhaps the odd brief interruption by a day closer to March normal temperatures, and it seems logical to suggest that the longer this spell continues, the more likelihood there would be for snow to affect your location, as it would be only a matter of time until the right combination of wind direction, frontal systems and temperature occur. However, we remember that March 2013 was generally quite cold and rather dry in quite a few places so that outcome is also possible.

My local weather has continued cold and dry with some mist from the open waters of local lakes in -7 C temperatures. Across the lower Great Lakes, very mild with flooding rainfalls on Tuesday, and this low appears headed northeast towards Quebec and eventually near western Greenland due to the large blocking high developing over Iceland next week.

Friday, 23 February, 2018

Forecasts for Ireland


ADVANCE ALERT for severe wintry weather conditions setting in on Monday and lasting at least through most of next week and perhaps returning at times in March. The earlier discussions posted about this spell are all considered to remain valid but if anything some of the latest guidance seems a bit more convincing, so there is certainly no reason to lower the probability of this severe wintry spell and increasingly, it appears that snow may be the dominant theme rather than just a dry but very cold outcome. Some very cold readings will probably happen after the snow, if skies clear and snow remains on the ground but the cold factor will be more of a combination of unusually low daytime readings (continuing at night) and strong winds.

TODAY ... Partly to mostly cloudy, moderate southeast winds 40-60 km/hr, highs 6 to 9 C. A few spots of light rain may brush by Atlantic coastal counties but it should remain dry in most places, and the best chance for any sunny breaks will be in the east and north.

TONIGHT ... Cloudy with some clear intervals, moderate southeast winds, lows about 1 to 4 C.

SATURDAY ... A rather cold start to the day with scattered ground frost, fog patches, but mostly just overcast, becoming partly cloudy to overcast, a little milder in west where highs 8-10 C, staying rather cool further east with highs 5 to 8 C. Winds south to southeast 40 to 60 km/hr.

SUNDAY ... Sunny intervals, lows -2 to +3 C, highs 5 to 8 C. Winds increasing at times to southeast 50 to 80 km/hr.

MONDAY ... Variable cloud, turning sharply colder during the day, possible snow or sleet showers by late afternoon or evening near south and east coasts. Morning lows about -1 C and afternoon highs only 3 to 6 C east, 5 to 8 C west. Winds east-southeast 50 to 80 km/hr.

TUESDAY ... Windy and very cold with risk of snow developing across eastern and southern counties, morning lows -5 to -2 C, afternoon highs -1 to +3 C, winds east to southeast 40 to 70 km/hr adding a chill factor (feeling like -6 C). Heavy snow could develop late in the day.

OUTLOOK ... Wednesday 28th and the first two or three days of March could produce an exceptionally cold and snowy period according to most of the guidance available. We cannot guarantee heavy snow at this early stage but it does seem very possible and amounts could be in the 10-30 cm range (at least). There is the threat of severe disruption if this comes to pass. Temperatures will be held down to near freezing in the daytime and may not fall a lot lower at night if there is a lot of cloud and snow but some parts of Ulster and Connacht might see lows of -8 C or lower if skies clear. Winds will increase at times to 50 - 80 km/hr from the east to northeast making it feel very cold (like -8 C). Even if this snow fails to materialize or remains very isolated, it will almost certainly be windy and very cold and the absence of snow would probably mean clearer skies and lower night-time temperatures, so it's a case of "choose your poison" in this remarkably cold spell.

It should be noted also that heavy snow is likely to hit parts of Britain and northern France, Belgium and Germany over this same period and European air and road travel may be severely disrupted.

Some guidance suggests outbreaks of heavy snow could turn to sleet or rain in parts of the southeast or in Britain by weekend of 3-4 March while other suggestions say this will stay in north-central France and further light snow could come and go in most of Ireland and parts of Britain while it stays quite cold (2-4 C). The duration of this cold spell is not very easy to estimate and there could be more cold spells even if it does warm up slightly, as the blocking pattern does not show signs of totally breaking down.

My local weather is also very cold and we had a fair amount of sunshine on Thursday with highs no better than -5 C.

Sunday, 25 February, 2018

Forecasts for Ireland


ADVANCE ALERT continues for very cold temperatures and potentially heavy snowfalls from Monday night to at least Friday of next week.

TODAY ... Sunny intervals, rather cold with highs 5 to 8 C. Winds increasing at times to southeast 50 to 80 km/hr. Somewhat more cloud in far west at times.

TONIGHT ... Clear and cold, lows -5 to -1 C.

MONDAY ... Sunny intervals to start the day, then variable cloud developing, turning sharply colder during the day, possible snow or sleet showers by late afternoon or evening near south and east coasts. Morning temperatures rising slowly to about 3 to 5 C, then falling during the afternoon in eastern counties, with a slight risk of snow or sleet showers by sunset, winds east-southeast 50 to 80 km/hr.

TUESDAY ... Windy and very cold with risk of snow developing across eastern and southern counties, morning lows -7 to -3 C, afternoon highs -1 to +3 C, winds east to northeast 40 to 70 km/hr adding a chill factor (feeling like -6 C). Heavy snow is likely to develop late in the day across Leinster. 5 to 15 cms possible there. This snow may be accompanied by thunder. Flurries or light snow could occasionally develop further south and west. Hail and sleet showers may be reported near sea level on east coast but snow will dominate any distance inland.

WEDNESDAY ... Windy and very cold with widespread snow, some of it heavy at times with thunder possible. A few sunny breaks in north Connacht, Donegal and north Clare, but flurries could invade there too, in winds east to northeast 50 to 80 km/hr. Morning lows generally -4 C but could be as low as -8 C in a few parts of the northwest. Afternoon highs -4 to +1 C. Snowfalls of 10 to 30 cms are possible in Leinster and 5 to 20 cms in some parts of Munster, inland southeast Connacht, and much of Ulster except likely less in Donegal. Near blizzard conditions are possible, and severe disruptions to travel may begin to intensify (with an extension of that in the following outlook).

THURSDAY and FRIDAY present a forecast challenge in that low pressure could be moving up from the south to clash with the very cold air, and this could set off a prolonged interval of heavy snowfalls, amounts between 10 and 50 cms are possible in this period but forecasts could change closer to the time. If the low does not get close enough to participate, it will be more of a continuation of the east coast and occasionally south coast snowfalls (perhaps 10 to 30 cm) in cold east to northeast winds 60 to 90 km/hr, so the low would be mostly a cause for snow to spread further west and north. Another variable is that the low could push close enough to Ireland by Friday to change the snow to sleet or rain, at least for a time, some model scenarios have this happening only near the southeast coast with snow gradually tapering off as the low moves away by Saturday.

The extended OUTLOOK is for one of two possible scenarios, depending on which group of guidance models proves to be correct. Either we see a gradual end to the cold spell with rain at times, fast melting of the snow pack with possible local flooding, and milder temperatures (to 7 C) or the cold hangs on in modified form, keeping the snow pack from melting very fast, in sleety bouts of light snow or rain and temperatures around 3 C. With that second scenario, cold air is not pushed very far north and could return for a second engagement around 7th of March or so.

At any rate, we can be fairly confident of extremely cold weather with localized snowfalls mostly in Leinster, south and east Munster and east Ulster for three or four days, and moderately confident of a heavy snowfall to follow that by Thursday night into Friday, but what happens from there on remains low confidence and so you could look for clarity on that by perhaps Thursday.

My local weather on Saturday turned out sunny in the morning then light snow developed, becoming a bit heavier tonight (3-5 cms expected here on Sunday before clearing again on Monday). It remains rather mild in eastern North America with rain spreading through the inland northeast today, highs on the U.S. east coast back above 10 C again.

Monday, 26 February, 2018

Forecasts for Ireland


ADVANCE ALERT for severe cold and heavy snowfalls in the coming week, with the risk of travel disruption and blizzard like conditions developing especially from Wednesday to Friday.

TODAY ... Some sunshine this morning, quite cold with southeast winds 40-70 km/hr adding considerably to the chill factor. Highs around mid-day 4 to 6 C, then temperatures are likely to fall sharply this afternoon in east, by evening west, as the really cold air arrives from Britain. It will become mostly cloudy and there could be occasional light snow or sleet although it will take a while to start this process.

TONIGHT ... Cloudy with a few clear breaks, occasional flurries and risk of some local accumulating snow near east coast, 2 to 4 cm. Lows -4 to -7 C colder in west and north. Winds east to northeast 40 to 70 km/hr adding chill (feeling like -10 C).

TUESDAY ... Variable cloud, windy and very cold, with outbreaks of snow (possibly sleet right along the east coast but snow more likely any distance inland), potential for 5 to 15 cms in Leinster, 3 to 10 cms in south and east Munster, traces to 3 cms further west and north. Winds northeast 40 to 70 km/hr, highs -1 to +3 C, and temperatures likely to drop during snowfall to -1 C. Snow may be accompanied by thunder especially near east coast.

WEDNESDAY ... After a very cold start (lows -11 to -5 C) becoming very windy with outbreaks of heavy snow likely, thunder possible, accumulations of 10 to 25 cms in parts of Leinster could be disruptive to travel, 5 to 15 cms in parts of Munster and east Ulster, tapering to trace amounts near west coast (but some bursts of heavier snow could reach as far west as Galway and Limerick). Highs only -4 to -1 C, feeling like -10 C in the wind which will be easterly 50 to 90 km/hr.

THURSDAY-FRIDAY ... A severe winter storm appears very likely, although those conditions may already be occurring by Wednesday in parts of Leinster. This storm is likely to spread to all parts of Ireland with strong east winds 60 to 110 km/hr (in exposed coastal east and south, more like 50 to 80 km/hr elsewhere), heavy snow, blowing snow and blizzard conditions especially over open rural and higher terrain. There is potential for 20 to 50 cms of snow during this period. Temperatures will be steady in the range of -2 to +1 C. Some guidance suggests sleet changing to rain could spread into south at least near coast, and this could eventually push further north. Other guidance still says that the cold and snow remain in place and continue with somewhat reduced severity into Saturday 3rd. ... This will obviously be very disruptive and travellers could be stranded if this comes to pass, keep in touch with the forecasts as better guidance becomes available mid-week.

OUTLOOK ... If the milder air and rain does spread over large portions of Ireland (considered about 50% likely at this point) the snow would melt rather quickly leading to widespread flooding, how severe depending on snow pack and rainfall amounts. Temperatures would rise to about 7 C and then there would be several days of unsettled weather with further rain or sleet and mostly southeasterly winds. If the snow hangs on and cold air stays in place, expect a much slower moderation with sleet or drizzle at times, highs near 4 C, and some chance of a return to very cold conditions by about the 7th or so (about a 40% chance of this outcome). There is even a chance of severe cold and further snow continuing for days beyond Friday 2nd (10% chance).

My local weather was cloudy with light snow on Sunday, about 2 cms fell and the high was just about +1 C, no real melting with that.

UPDATE _ Tues 27 Feb 2018 _ 7:30 p.m.
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Snow is likely to become heavier and more widespread after midnight, with present scattered outbreaks continuing to drift west, while more extensive sea-effect streamers will form as colder air aloft reaches the Irish Sea and the wind gradient picks up overnight. Would not be surprised to find 5 to 15 cm snowfalls in Leinster by the morning commute.

Little change to earlier forecast from new guidance, will just mention that Wednesday likely to see continuing widespread snow showers, heavy at times, and further accumulations 10 to 20 cm, tapering to trace amounts to 3 cm on west coast. The main reason for the update was to give any new perspectives on the Thursday-Friday snow potential and whether that would change over to rain at least in the south. The latest guidance seems slightly more supportive of the idea that heavy snow would continue well into Friday and any change would be limited to south coast, most of lower elevation Kerry and perhaps a few places a little further north (inland) but the snow would end without much if any liquid precipitation or thawing, although temperatures may creep up slightly on the weekend allowing a slow erosion of the snow depths likely to be attained by mid to late Friday.

So at this point I am still thinking blizzard-like heavy snow is possible and 20 to 50 cms may accumulate over that period, but as we should have better guidance available by the morning and we still have Wednesday's significant event to come, there is a wide range of possible outcomes for snow, best bet is around 25 cms on the average (10 to 15 further northwest) in many places and 40 cms not uncommon in central and southeast Leinster.

Next update will be the morning forecast at the usual time (0700h to 0730h).

Thursday, 1st of March, 2018

Forecasts for Ireland


ALERT continues for accumulating snowfall today mostly in counties of north Leinster, east Ulster, and inland east Connacht, but with some risk near south coast also. The intensity of snow will likely be somewhat less impressive than yesterday with 5 to 10 cm further amounts. ADVANCE ALERT for heavy snow covering most of the country (possible exceptions of northwest coast and parts of Ulster) tonight and Friday, amounts could be as heavy as 20 to 40 cms. ADVANCE ALERT for very strong winds and coastal flooding on south coast Friday afternoon, evening and overnight (70% risk, could be less intense depending on storm track evolution).

TODAY ... Mostly cloudy with a few sunny breaks inland south and coastal west, northwest. Outbreaks of snow mostly from Dublin west and north, 5 to 10 cm additional likely with potential for 15 cm in a few places. Low overcast may develop later with strong east to southeast winds (reaching 60 to 110 km/hr) and occasional snow or blowing snow becoming more widespread by late afternoon and evening. Highs -3 to +1 C.

TONIGHT ... Very windy and cold with snow, heavy at times, spreading north. Occasional thunder likely especially in southeastern counties. Temperatures steady -3 to -1 C for most, near -5 C or lower in any remaining clear areas in northwest. Winds southeast 70 to 110 km/hr in exposed southern and eastern locations, otherwise 40 to 70 km/hr. Wind chills near -10 C. Snowfalls of 10 to 15 cm possible by morning in much of the southern half of Ireland, 5 to 10 cm in some north central counties, probably little accumulation aside from isolated sea effect 2 to 4 cm in north.

FRIDAY ... Heavy snow will continue, and may become mixed with ice pellets near south coast. There is a slight risk of freezing rain near the southeast coast. Snow will become rather wet clinging to exposed surfaces, tree branches could be brought down causing scattered power outages. Snowfalls of 15 to 30 cm (additional) are possible, but there may be isolated patches of lesser amounts for example to the northwest of any higher terrain. Snowfalls of 5 to 15 cm are expected to reach all northern areas but there is some risk of either more or less depending on the exact track of storm "Emma." Temperatures in most places will be steady in the range of -2 C to +2 C with the milder readings near the south coast and in any areas remaining largely dry in the northwest. Coldest locations will be inland southeast northwards into east Ulster. Blizzard conditions with severe blowing snow are possible in open rural areas especially.

FRIDAY NIGHT ... The snow may taper off to flurries for many, although bands of moderate snow may continue to develop at times from the Irish Sea inland. A further 5 to 15 cm could fall in some places. An interval of somewhat milder temperatures may brush the southwest coasts and readings of 4 or 5 C are possible for a time with rain instead of snow, but further inland in Cork and other parts of Munster, the snow may change to sleet for a time and back to snow as this milder sector moves past. Winds will back to northeast and will moderate to about 50 to 80 km/hr, except for some storm force gusts possible in Kerry (east to southeast 80 to 120 km/hr). High tides may bring coastal flooding from Wexford around to Kerry and tides will be unusually high on the east coast also.

SATURDAY ... Some further outbreaks of snow or sleet are likely, 2 to 5 cm amounts, temperatures steady -1 to +3 C. There may be slight melting of any heavy snow packs but also some further blowing and drifting in colder areas. Moderate northeast winds may pick up again later in the day.

SUNDAY ... The outlook is rather uncertain with conflicting signals, but mild air could try to ooze its way into southeastern coastal districts while many other places stay rather cold with further mixtures of wet snow, sleet or coastal rain. Temperatures are likely to creep up slightly to the 1 to 4 C range.

FURTHER OUTLOOK ... Again, there is considerable uncertainty but many signs that the cold air will not be entirely vanquished by any slight warming trend and that temperatures could come back down somewhat during next week with further outbreaks of sleet or snow.

Watch for an update about the potential heavy snowfall event (and blizzard) around 7 to 8 p.m. with the latest guidance as the storm should be approaching around then and some of the uncertainty should be resolved.

My local weather on Wednesday was cloudy but rather bright at times with glimpses of sunshine, and a somewhat milder high of 3 C.

The eastern United States and Canada are bracing for the effects of the Atlantic "retrograde" regime which is going to club to the ground the current mild spell as colder air spills south into Quebec from Greenland. That's going to lead to a coastal "nor'easter" storm by Friday and Saturday with strong northeast winds, sleet or wet snow in New England, and much colder further west than today's highs near 15 C.

Friday, 2 March, 2018

Forecasts for Ireland


ALERTS continued for heavy snow and strong winds across many parts of the south and east. ALERT for coastal flooding may be somewhat downgraded but be vigilant (most model guidance has slowed or weakened the core of Emma, this does not mean however that the storm is weakening, because much of the energy of this storm is the easterly flow that can maintain itself longer with a weaker core to the low.)

FORECASTS ...

TODAY will continue to produce locally heavy snowfall in some parts of the southeast, central Leinster, and scattered portions of the midlands and southwest, up into Galway. There are about equal areas of lighter snowfall, those tend to be in the lee of higher ground (inland southeast) but occasionally these areas will see bursts of heavier snow. Further accumulations will therefore vary over a large range, your best bet is to double what you have already had from mid-day yesterday at your location -- this may be anywhere from 2-5 cm in light snow areas, to 30 to 50 cm in heavy snow zones. Winds near the east coast will be easterly 70 to 100 km/hr and these strong winds are making considerable progress inland in central regions, where snow has been heavy, severe blowing and drifting has already begun and will continue. Near the south coast, winds are likely to fluctuate more between 40 and 70 km/hr and drifting will be more moderate. Low snowfall zones will also tend to be sheltered from strong winds (there may be exceptions near boundaries between heavy and light snow). And to complicate matters further, parts of the north will remain almost snow-free while other places get sudden blasts of snow from streamers that are affecting parts of east Ulster. Temperatures for all will fluctuate between -1 and +1 C. There will be some limited sleet or even rain near south coast and in pockets on the east coast too, but no major changeover is expected, especially with the weaker depictions for storm Emma on the new guidance.

TONIGHT ... Snow will begin to taper off to light snow or flurries except in parts of the inland south and west where a further 10 to 15 cm may occur, however, there could be some ongoing heavy snow streamers in central Leinster. Winds will tend to back to northeast 40 to 70 km/hr. An interval of somewhat stronger winds may brush past Kerry affecting the southern portions as well as southwest Cork. Peak gusts may reach 100 km/hr. Coastal flooding is still possible although the risk seems a bit lower given the weaker circulation around the core of Emma. Lows generally -7 to -4 C north, -3 to +1 C south.

Note: If you read to here earlier, then I was attempting to edit in the rest of this forecast, when my own power went out (no obvious reason as the weather here is calm and dry), have just gotten back on line now after an outage of 90 minutes or so.

SATURDAY will be mostly overcast with a few sunny intervals developing mostly in the north, moderate northeast winds, and a few outbreaks of sleet or light snow possible in the east and south. Highs 2 to 5 C. There will be some melting of snow in urban and coastal areas, and some ponding of meltwater will begin.

SUNDAY will continue overcast with further outbreaks of mixed sleety precipitation, light to moderate east winds and temperatures steady 2 to 4 C, except somewhat colder in clear spots further north. There will be a lot of slush developing in towns and cities especially, partial melting of the heavier snowpacks, and considerable ponding of water. Smaller streams may show some signs of flooding in coastal lowlands.

NEXT WEEK will continue rather cold and unsettled at times with outbreaks of sleet or snow, one of which may become a little heavier around Thursday, in generally northeast winds. Highs each day 4 to 7 C. The slow melt will continue and there will be some problems with ponding and minor flooding here and there, hopefully the pace of the melt will not lead to serious flooding but the situation should be closely watched.

At some point most guidance is suggesting an interval of milder weather and a return to more normal March weather conditions. At that point, if there has not been substantial snow melt, flooding would become a concern. Higher elevations will retain their snow packs all week and might begin to produce heavy run-off at any point when temperatures in lower elevations reach 10 C or higher, it will be 3 to 6 C "up top" where the snow would be deeper at that point. If there was a heavy rainfall that might be the deciding factor. Let's hope for a dry spell to follow the cold, but it often doesn't happen that way.

My own weather was quite bland on Thursday, overcast and a bit milder than recently at 4 C. All the remaining snow on local roofs found it ideal sliding weather so like a few other people I found most of that snow in my way when I first tried to go outside. We still have about 20 cm snow pack here with huge piles of cleared snow along the sides of roads and laneways.

I may post an update later, if my power stays on. We tend to get occasional outages here, any random snow slide, tree falling on a line, or car going into a power pole will knock out service for an hour or two and being in an isolated setting, there are no plan B options for internet connection if my modem isn't getting power, no internet source on any battery-driven device. I should get somebody's phone number perhaps.